A weekend of D&D in Thalassia

The following mini-campaign, adventure path, or simply campaign setting was the basis for a weekend of D&D recently. Thalassia is an ocean world in which great floating cities vie for control over the planet. Take elements from this mini-campaign into your own game, create your own mini-campaign based on the article, or run this adventure path as written!

I ran 16 hours of games set in Thalassia, four adventures at four tiers of play. Here’s a brief overview of the four adventures:

• Level 4: Intrigue at the Congregation. The characters fall into a web of intrigue and deception at the Congregation, the annual gathering of the great powers of Thalassia.
• Level 8: The Okeanus Sceptre. The characters retrieve a relic of the Old Gods from the ruins of Calathis at the bottom of the sea.
• Level: 14: Defense of Shardi’nam. The characters defend an outpost against overwhelming odds.
• Level 20: Shadow over Thalassia. The characters hunt the Ghannabar — a devil among the Old Gods, this malice takes the shape of a dragon turtle.

Character Motivation

Before starting the mini-campaign, hand the players a character motivation for their characters. We can introduce this party motivation at the beginning of our session zero. That way, players build their characters with this cooperative motivation in mind:

You and the other characters work together to protect Thalassia and its people.

During character creation, the players can decide to add nuance and detail to this motivation. For example, they might want to play a party of daring explorers, charting the most dangerous areas of Thalassia. Or they might be adventurer-diplomats, looking to make Thalassia a more just and equal society.

Thalassia’s Truths

The following things are true and known to the characters at the beginning of the campaign:

• The Ocean is Everything: Thalassia is a planet of a vast and boundless ocean. Land is scarce, precious, and often perilous. The civilizations of this world depend entirely on the sea for their survival, resources, and commerce. Every city, every race, and every creature is irrevocably tied to the ocean’s whims.
• Perils and Promises of the Colony. The only landmass, known as The Colony, harbors an anomaly that gives rise to all arcane magic. This anomaly makes the land dangerous but also invaluable. Control over The Colony means control over magic itself, and thus it is heavily contested and fraught with conflict.
• The Anglo-Fishian Church Rules. A single religious institution, worshiping majestic sea spirits as gods, dominates the spiritual landscape of Thalassia. This church’s influence extends into the political sphere, where it plays a critical role in the governance and conflicts of the great cities.
• The Great Cities are Autonomous Powers: Each of the major cities—Emnor, Nod’nol, T’hali, New Calath, Lisandril, and Rathun—operates almost like a sovereign state, with its own culture, governance, and agenda. Alliances are as fluid as the waters they are built upon, and politics are as deep and shifting as the tides.
• Race Relations are Tense and Complex: The major races of Thalassia—Merfolk, Aasimars, and Grungs—coexist in a delicate balance. While merfolk are prevalent, aasimars are viewed with a divine mystique, and grungs, often seen as second-class citizens, are on the brink of rebellion against oppressive forces.
• The Myth of Calathis: In Thalassia, the underwater city of Calathis exists as a legend, whispered in taverns and debated by scholars. Some claim it is a repository of ancient wisdom lost to the ocean’s depths, while others believe it a fanciful tale concocted by mariners and poets. Its true nature remains a tantalizing mystery, luring the brave and the foolish alike into the deep.

The Villains of Thalassia

Three major villains drive the events of this campaign. We can use them flexibly, as villains react to the choices the characters make.

• The Anglo-Fishian Church. A dominant religious institution that venerates various sea creatures as gods. The church is divided into sects, each worshiping different sea deities like sharks, anglerfish, etc.
• Rathun, the Red Tide. A militaristic city-state with a powerful navy, known for its ruthless expansion and enforcement of maritime law.
• The Ghannabar. An ancient dragonturtle of Thalassia’s pre-history, yearning to return to the world and destroy civilization.

Other Factions of Thalassia

The following factions can play a role in the mini-campaign in Thalassia. We can use them as group patrons for the party, as allies or adversaries, or to quickly give an NPC a relationship to the politics of the world.

The City-States

1. Emnor, City of Glass: Known for its advanced technology and water purification systems. Politically neutral and a hub for diplomacy and trade.
2. Nod’nol, City of Gears: A powerhouse in engineering and mechanics, this city is always on the move and boasts massive factories and a huge labor force.
3. T’hali the Veiled Cliffs: Known for its recreational pursuits and as a haven for artists, gamblers, and entertainers.
4. New Calath, Hope of the West: A thriving trade center in a hot, sandy environment. It is the largest city and acts as a cultural melting pot.
5. Lisandril the Forever City: An ancient matriarchy, steeped in tradition and known for its strong government and spiritual leadership.
6. Rathun the Red Tide: A militaristic city-state with a powerful navy, known for its ruthless expansion and enforcement of maritime law.

Other Factions

1. The Anglo-Fishian Church: A dominant religious institution that venerates various sea creatures as gods. The church is divided into sects, each worshiping different sea deities like sharks, anglerfish, etc.
2. The Knowing Hands: A network of information brokers and artifact traders, influential in the realms of academia and black markets.
3. The Colony Settlers and Rebels: Consists of both the colonial authorities who govern the only significant landmass (a source of wood and arcane magic) and the rebels (primarily Grungs) who oppose their rule due to harsh conditions and exploitation.
4. Mercantile Guilds: Powerful trading guilds that control various aspects of commerce in Thalassia, often having their own agendas and influence within the political landscape.
5. Pirate Leagues: While not formally recognized, these leagues hold significant power in less regulated waters, sometimes clashing with city-states like Rathun the Red Tide or making illicit deals with others.

Adapting to the characters

Use the information from this article to help players build characters (for example for a weekend of D&D) with deep ties to the setting of Thalassia. For example, characters might have history with one of the villains, their backstory might be related to one of the truths, or even to a villain.

We can also pick and choose factions, secrets and villains to foreground in our campaign after we know more about the characters. We can grab onto hooks, relationships, and mysteries in the characters’ backstories and motivations, and build them into the campaign outline.

Either way, in other articles, more details about the four adventures in a nautical mini-campaign set in the ocean world of Thalassia will follow.